At a time when the British monarchy confronts an uncertain future, King Charles III was crowned Saturday at Westminster Abbey in a ceremony based on ancient customs.

When the event began in front of more than 2,000 guests, including international leaders, nobles, and celebrities, trumpets rang out within the historic monastery and the audience sang 'God save King Charles.'

Moments at King Charles' Coronation

Outside, hundreds of military, tens of thousands of onlookers, and a sprinkling of protestors assembled along the path taken by the monarch in a gilt-trimmed, horse-drawn carriage from Buckingham Palace.

The royal family and administration see the event, code-named Operation Golden Orb, as a show of legacy, tradition, and spectacle unparalleled in the world.

The ceremony was anticipated to be viewed by millions, but the wonder and respect that the ritual was intended to elicit are mostly gone - and many people welcomed the day with apathy.

NBC New York reports said the chapel was buzzing with excitement as people came, and it was adorned with fragrant flowers and bright hats. US First Lady Jill Biden, French President Emmanuel Macron, Canadian Prime Minister Justin Trudeau, eight current and previous British prime leaders, as well as Judi Dench, Emma Thompson, and Lionel Richie, were among those there.

Millions of fans from all around the world tented overnight along the 1.3-mile (2-kilometer) path taken by the monarch and his wife, Camilla, to approach the monastery.

Charles, dressed in red and cream robes, swore on a Bible that he is a "genuine Protestant" at a classic Anglican ritual slightly adjusted for modern times.

However, for the first time, a preface to the coronation oath was added to state that the Church of England "will seek to foster an environment in which people of all faiths and beliefs may live freely."

Prime Minister Rishi Sunak read the epistle from the King James Bible. A gospel choir sang a freshly created "Alleluia," and female clergy participated in the event for the first time.

British rulers have been crowned in spectacular rituals that guarantee their right to reign for at least 1,000 years. Since his mother, Queen Elizabeth II, died in September, Charles has had no executive or political power, and the service is now solely ceremonial

The king remains the head of state and a symbol of national identity in the United Kingdom, and Charles will have to struggle to unify a multicultural nation and keep the monarchy relevant at a time when support for it is dwindling, particularly among younger people.

The coronation procession meandered 5 miles (8 kilometers) through central London in 1953, with temporary stands added to increase seating capacity to more than 8,000. Aristocrats donned crimson robes and coronets, and an estimated 3 million spectators cheered for the gorgeous 27-year-old queen.

The procession path was reduced this time, the coronation service was cut to less than two hours, and 2,300 invitations were handed out to global monarchs, chiefs of state, public employees, vital workers, and local heroes.

Prince William, the heir to the throne, his wife, Kate, and their three children were all present. Prince Harry, William's younger brother who has openly feuded with the family, arrived alone.

The coronation ceremony, themed 'Called to Serve,' opened with one of the congregation's youngest members, a kid chorister, greeting the monarch. Charles answered with, "I'm not here to be served, but to serve."

The time is intended to emphasize the value of youth - it is a fresh addition to a service filled with the rituals that have passed power down through the years. The two-hour ritual reached a symbolic high point halfway through when Archbishop of Canterbury Justin Welby put the solid gold St. Edward's Crown on the monarch's head. Trumpets were blown and gun salutes were fired across the United Kingdom.

A day after the golden spectacle of King Charles III's crowning in an ancient religious ritual, thousands of picnics and street celebrations were conducted across the United Kingdom in his honor, with no formal invitation necessary.

In a statement issued Sunday, Charles and Queen Camilla said they were "deeply moved" by the celebration and "profoundly thankful both to all those who contributed to make it such a magnificent event - and to the very many who went out to express their support."

Prince William stated at the performance on Sunday that service was at the core of the "magnificent" coronation events, and that his father's first words upon entering Westminster Abbey were ones of duty.

Katy Perry, Lionel Richie, and Take That headlined the performance on Sunday. The newly-crowned monarch and his wife looked to enjoy the event when Richie played 'All Night Long,' even standing up and swaying to the music at one point.

Several members of the royal family, including Princess Charlotte, 8, and Prince George, 9, waved Union flags alongside the 20,000-strong audience assembled on the castle's east terrace.

Charlotte and her mother, Kate, Princess of Wales, sang along as Perry performed her pop song 'Roar' in a gold foil ball gown.

Tom Cruise emerged in a pre-recorded video message, saying, "Pilot to pilot. Your Majesty, you are welcome to be my wingman at any moment." The Royal Ballet, Nicole Scherzinger of the Pussycat Dolls, opera singer Andrea Bocelli, and British band Take That also performed on the mixed program, s per CBS News.

Miss Piggy and Kermit the Frog even made a cameo, teasing host Hugh Bonneville. Valent Cheung and his fiancée turned up to applaud the new king with the neighbors who welcomed them when they relocated from Hong Kong, under a beautiful green canopy in Regent's Park in London. Tino, their faithful and "royal" fluffy white dog, was decked out in a small purple crown for the occasion.

In honor of the newly crowned king, the Union Jack was placed on houses and flown from tables and trees from tiny settlements to the capital. It was printed on napkins and tablecloths, as well as caps and bow ties. Others dressed the flag's colors like a uniform, covering themselves in red, white, and blue from head to toe and up to their fingernails.

The community gatherings, part of a British custom known as the Big Lunch, were designed to bring neighbors together to celebrate the monarchy's re-establishment even as support for the monarchy dwindles.

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King Charles Coronation Sparks Protests

Meanwhile, anti-monarchists decried the heavy-handed police at King Charles' coronation on Sunday, saying there was no longer a right to peaceful protest in Britain after scores of protestors were arrested and kept late into the night.

While hundreds of royal fans gathered in the city for the event on Saturday, police detained Graham Smith, head of the Republic group, and scores of others in central London, arguing their obligation to avoid disturbance trumped the right to protest.

Members were freed late Saturday evening after roughly 16 hours in jail, according to Republic. The Metropolitan Police in London said on Sunday night that 64 arrests had been made on Saturday for offenses ranging from disturbance of the peace to conspiracy to make a public nuisance.

One was accused with violating the public order act, while others were freed on bail. Police said they understood the public's outrage over the arrests, but that they responded after receiving intelligence that protestors were intent to disrupt the coronation parade.

London police chief Mark Rowley warned on Friday that if demonstrators sought to "obstruct people's enjoyment and celebration," officers would take action, adding that there would be a "very low tolerance" for disturbance.

Per Reuters, a new policing legislation approved last year, and a public order statute that went into effect on May 3, gave police more ability to suppress protests.

Tens of thousands of people gathered to see newly crowned King Charles and Queen Camilla as they travelled in a state coach back to Buckingham Palace following Saturday's ceremonies at Westminster Abbey.

Hundreds of republicans booed and waved banners saying "Not My King," indicating that not everyone who came to see was there to applaud Charles.

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